They arrived at the Crystal Empire stop and both walked off the train. Starlight got off first and offered some supportive magic to Sun as she got off.
Sunburst snorted at the unasked for assistance. "What is that for? Neither of us are hurt, or tired." She stepped down under her own power. "I can manage that."
"Sorry." She slid in at Sunburst's side. "You've felt fragile. Just... caring, is all."
"Um." Sunburst looked to the sky a moment. "Thank you..." They took a deep breath. "Alright. We're here... I've been feel-- We're in everypony's way." They moved quickly off the platform with Starlight trailing behind. "Right."
Standing down at street level, with far less traffic being blocked, Sunburst nodded at Starlight. "I want to show you."
"I want to see it... even if just a peek. The curiosity is burning over here." She waggled her brows. "Nothing untoward, I just want to know."
Sunburst scuffed a hoof, suddenly self-conscious under Starlight's earnest gaze.... They led the way swiftly to their home and opened the door for both to head inside.
Halting in the cleaned living room, Sunburst inhaled slowly then lifted their tail, angling hindquarters to reveal subtle udders despite lacking a true mare's robustness. Starlight's eyes rounded further noting the sheath yet absence of any testicles.
Sunburst flushed. "I-I don't know quite what you pictured with me being intersex." They bit their lip shyly. "Externally I have this delicate balance, but I suspect deeper complexity internally regarding, um...plumbing?"
"Sunburst, hush, it's ok!" Starlight touched their shoulder, smiling in solidarity if still processing. "You're wonderful no matter what parts or pieces make up the whole, alright?"
Starlight reached out a hoof, then hesitated. "I'm being rude. Look, no touching without permission, duh Starlight."
Sunburst snickered at her self admonishment. "Um, so, speaking of looking. How do I... look?" Sunburst turned in place, making it all that easier to see all the parts of them. "I feel... great, but also strange? Strange, as in... most ponies are not this."
"No, they are not." Starlight nodded with stiff muscles. "But you're still you, which means you're still my friend." She went in to bump heads, angling her horn to not poke Sunburst along the way. "So, stallion and mare. Best of both worlds, huh?"
"Or worst. Depends on which way you look at it." Sunburst shook themselves out gently. "I... mentioned I was 'above' pronouns... But I think that's not entirely true."
Starlight parked an ear and stepped back. "Oh, well, tell me. Which should I be using?"
Sunburst waved over themselves. "I'm neither, both, but like being a mare casually I think... So She, or they?"
Starlight lifted her shoulders. "Works for me. So I can call you a sister?"
Sunburst snorted softly. "Technically correct... Um..." They cleared their throat. "Starlight."
"Yeah?" She angled her head, hearing that thick question. "What's up?"
Sunburst danced in place. "I feel like I'm making up for lost time. I feel alive in a way I hadn't been."
"Great." Starlight sat down. "But I have no idea what you mean. Use your words, Sunny."
"I have a drive."
Starlight blinked at the admission. "A drive for...?"
"I lived my entire life not caring, but now I do... Um... That's normal, right?" Sunburst rubbed behind their head awkwardly. "You care, right?"
"Sunburst, you are being super vague right now." Starlight stood up. "I'm an adult! If you trust me, go ahead and say what you mean, bluntly. Be as blunt as you want."
"Part of me is imagining what it'd be like to try all my parts on ponies I see." They let out a tired sigh. "I had been living an asexual life until now, and... now not. It's... I feel like a pervert."
"Oh!" Starlight swatted at them with a smirk. "I thought it was way worse than that."
"Um?"
"Not putting you down." She touched her nose to Starlight's tense cheek. "That is a normal pony thing. So is not thinking about it. You got yourself put back together, and, well... A pony that was missing a leg that got their leg back, might take off running if they suddenly could, right?"
Sunburst exhaled in palpable relief. "So you're really not disgusted or judgmental here?"
Starlight gently punched their shoulder with a smirk. "Sunny, when Pinkie and I gave Discord that truly terrifying makeover, did you react in disgust or judgment?"
"I bolted for the hills," Sunburst snickered, imagining the collaborative chaos.
"Exactly! Yet here I still stand with you." Starlight gestured broadly. "Point is, I've faced a lot weirder in stride. And this..." She patted their shoulder tenderly. "Is just my friend embracing the whole beautiful spectrum of who they are at last. What's to judge in that?"
Tears pricked Sunburst's eyes as she wordlessly squeezed Starlight close. Almost instinctively the hug lingered to a compelling extent before they gently disengaged.
Starlight cleared her throat, grinning. "Besides, if anything that drive will be a bonus getting all the cute ponies now!" Her laughter lifted them further as Sunburst relaxed fully.
Sunburst cocked a brow. "Star."
"Yeah?"
Sunburst pointed at her. "You're a cute pony."
Starlight blinked, red creeping out from her nose outwards across her face. "Oh... Sun..." She turned away, hiding her radiating heat. "Thank you?"
Sunburst took an awkward step back. "Too strong? Sorry! I just meant... You're an attractive mare with an appealing mind, body, and magical abilities." With each word, Starlight's blush only got worse. "By the way, my magic got better! With my insides put back together, the block's gone! I can cast spells properly. Maybe as good as you?"
Starlight's blush faded instantly as she whirled on Sunburst, doubting brow high. "Big words. Are you ready to stand behind them?"
Sunburst advanced towards the door. "Gladly, and I could use some magic pointers. I just... couldn't before, and now I can."
"Well, those urges I'm ready to face." Starlight's horn glowed dangerously as she followed Sunburst out of their house. "I'll beat you up and show you how to fight better and we'll keep on doing that until one of us gives up."
Sunburst laughed tensely. "Yeah, fun... I was more hoping you'd spend time showing me practical magic?"
Star lowered both of her brows. "Are you implying combat isn't practical? One of the most practical out there... But fine, tell me what kind of magic you want to practice first."
Sunburst led the way to the stadium where the Equestria Games had been held. "Good, not too many around." They took a firm spot. "I'm going to show you spells I know. I know, um... a lot of them, but I never got to cast most of them."
Starlight sat a short distance away. "Show me what you have. You made it sound like this was a night and day thing, so... wow me."
Sunburst settled into a power stance, inhaling slowly. This would be her first real test actually harnessing the arcane torrents now coursing freely within since her vision's clearing. But under Starlight's expectant gaze, nerves settled into assurance.
Her horn lit, casting pairs of the little illusory assistants she'd struggled so painfully to manifest before. Now six clustered around her, waving cheerily before merging into a sizable simulacrum of Spike. It flexed and posed dramatically, eliciting Starlight's laughter.
Grinning herself, Sunburst dismissed it then lit up attempting spellwork once completely beyond her. The air rippled as she strained to open a small, unstable portal through which bewildered crystal palace staff could be glimpsed. Starlight's eyes rounded, impressed. She was really putting these new magical muscles through their paces!
Panting lightly from the exertions but floating with accomplishment, Sunburst trotted over. "Well...how'd I do for a new pony?"
"Not bad... But you already wrote to me about the illusionary doubles. Let's see something else." Starlight nodded, self-pleased at her logic. "Sparring is still an option."
Sunburst laughed tensely, thinking something else up. "How about... this!" they launched a new spell, horn glowing brilliantly with new runes as they gave Starlight much the same beard Sunburst had.
"What'd you do? I don't see anything?" Starlight looked around for the result of the magic. "Did it fail?"
Sunburst pulled out a mirror with their magic, hovering it over for Starlight to see.
She turned and jumped at the strange face she saw. No, that was her own face, bearded. "Sunburst!" She raised a hoof to feel the extra fuzz. "Not my style. Still, impressive. Adjusting pony fur patterns can be very tricky at the best of times." She wiped the beard away as if her hoof were simply absorbing the magic, if one ignored her glowing horn.
"Can you do something physical? Make something with real mass or shove something with the same?" Starlight clapped her hooves. "Get down and dirty with it."
Sunburst grinned and swept a hoof across the open field with a burst of arcing luminosity. In her wake sprouted towering jagged walls of scintillating opalescent crystal. The barriers curved as they rose, interweaving together into a passable scaled down replica of the palace itself jutting fiercely into a twilight sky.
"That...is damn impressive," Starlight admitted staring at the quintessentially crystal pony magic pulled off. "Just don't get too ambitious or we'll have Cadance throwing us into a lake or something for messing with her views."
She trotted along the sparkling effigy, rapping it with a hoof. Eerie resonances echoed back, hinting at an almost eerily convincing echo of the real deal somehow immortalized here now at Sunburst's whim. "This has to go." With a firm toss of her head, she banished it away into so much shattered glass fragments that faded away moments later. "Still, great! That was way more... Love it."
Sunburst smiled with blushing pride. "Thank you. So, how can I be better?"
"Great question." Starlight came in with a wry smirk on her face. "You're leaking." She reached up a hoof to tap at Sunburst's horn. "You're not used to that much throughput, and it shows. I can feel it leaking out the sides. You have to practice going high-output without letting a drop get out except where you're aiming."
Sunburst pinned her ears back. "I hadn't even noticed."
"A lot easier to see from the outside." Starlight nudged against Sunburst. "Good thing you have a magic buddy, huh?"
"Yeah." Starlight leaned back against her. "It is, um... But how long can you stay." They grabbed Starlight from the side. "Please stay."
Starlight squeaked at the grab, but it turned into a warm laugh. "How do I say no to that? I'll write Twilight, letting her know what's going on. I doubt she'll be too mad with me giving magic lessons to a friend."
So the magic lessons came to an end. Starlight stifled a yawn as the two ambled back the darkened streets toward Sunburst's cottage. Eventful days were clearly catching up now that exhilaration ebbed. Still, she nudged her companion playfully.
"So roomie, know any good late night diners around here? All that magic really works an appetite up!"
As they rounded the last corner though, she backpedaled slightly, struck by suddenly presuming sleepover arrangements.
"That is uh, if you don't mind a houseguest for my stay? I can always get a room too, no pressure!" She waved a hoof, feeling oddly flustered again under starlight alone with this newly intensified version of her oldest friend.
Sunburst simply shouldered the door open with a knowing beam. "Oh, I'd never abandon my guest to some stuffy hotel! Now, let me regale you with a grand tour of my luxurious abode, darling!"
Laughing, Starlight let herself be ushered playfully forth, lingering tension dissipating under familiar antics. "I didn't notice before..." She poked around Sunburst's home. "You've cleaned up." She sniffed the air. "You've really cleaned up."
Sunburst darkened mildly. "Um, why did you sniff like that?"
Starlight rolled her eyes. "Look, there was a smell before. Now there isn't." She hopped up onto a chair and sank to her haunches. "This is really working out for you."